But about $4.4bn was earned through kickbacks on humanitarian goods supplied through the UN's oil-for-food (OFF) programme, they said.

Previous reports such as the CIA's - produced by a 1,200-strong team led by Charles Duelfer, one of four witnesses testifying - have alleged that firms, government ministers and senior UN officials benefited from the corruption.

Among them are the former head of the oil-for-food programme, Benon Sevan, and a number of French politicians and companies. They have denied the allegations.